Apple Computer and Sony are to appear in court over claims that their respective music download sites have been deceitful and have forced consumers to buy products because they are tied together.

French consumer association Union Federale des Consommateurs-Que Choisir has launched legal action over the two companies' proprietary music formats, claiming that the respective digital rights management used by both Sony and Apple, which prevent songs bought from their online music shops from being played on other manufacturers' media players, is limiting consumers' choice.

The consumer group announced that it would take legal action against the pair after conducting interoperability tests last year between a selection of download services and digital music players. The group criticized the two companies' lack of interoperable DRM.

"The total absence of interoperability between DRM removes not only consumers' power to independently choose their purchase and where they buy it from but also constitutes a significant restraint on the free circulation of creative works," the group said.

Despite railing against Microsoft's similar locked-down stance on interoperability during its compatibility testing and indicating that the company was in its legal sights, UFC-Que Choisir has not filed suit against the Redmond, Wash.-based software behemoth.

The suit was filed against Sony France and Sony United Kingdom, as well as Apple's French unit and its iTunes Music Store. Apple's case will be heard in a Court of First Instance in Paris; Sony's will be held in a Nanterre court. Both cases are expected to be heard later this year.

Apple declined to comment. Sony did not immediately respond to requests for comment.

This isn't the first time the issue of interoperability in music has made its way through the French legal system.

Recently, VirginMega, a subsidiary of Virgin Group, brought an anticompetition case against Apple before the French Competition Council. The case was rejected late last year.